Concrete composition

Abstract

High-strength concrete comprises aggregate, portland cement and alkali metal or alkaline earth metal polysulfides.

What is claimed is: 
     
       1. A concrete composition comprising a major portion of aggregate, from about 6 to 15% by weight portland cement based on aggregate, and from 1.5 to 6% based on aggregate of an alkali metal or alkaline earth metal polysulfide. 
     
     
       2. The composition of claim 1 in which the polysulfide is calcium polysulfide. 
     
     
       3. The composition of claim 2 in which the ratio of coarse to fine aggregate is in the range of 1:1 to 4:1. 
     
     
       4. The composition of claim 2 in which the weight ratio of cement to polysulfide is from about 4:1 to about 2:1. 
     
     
       5. A concrete composition consisting essentially of about 6 to 15% of Portland cement and from 1.5 to 6% of an alkali metal or alkaline earth metal polysulfide, the remainder comprising a combination of fine and coarse aggregate, said percentages, being based by weight, upon said aggregate. 
     
     
       6. The composition of claim 5 wherein said polysulfide is calcium polysulfide. 
     
     
       7. The composition of claim 5 wherein said aggregate is a mixture of coarse and fine aggregate having a weight ratio of the former to the latter in the range of from about 1:1 to 4:1. 
     
     
       8. The composition of claim 5 having a weight ratio of said cement to said polysulfide in the ratio of from about 4:1 to about 2:1.